Ball joint

ABSTRACT

The present invention pertains to a ball-and-socket joint ( 1 ), comprising a sleeve ( 2 ) or a pivot ( 3 ) with a partial spherical surface ( 4 ) and with a bearing shell ( 5 ) surrounding the said partial spherical surface ( 4 ) in a positive-locking manner with a hollow spherical bearing surface ( 6 ), which is arranged in a two-part housing ( 9, 10 ), whose housing halves ( 9, 10 ) have locking elements ( 15, 16 ) with detents ( 17 ) and locking grooves ( 18 ) mutually engaging one another, which lock the two housing halves ( 9, 10 ) with one another in a relatively immovable manner in the direction of the longitudinal axis ( 13 ) of the sleeve ( 2 ) or of the pivot ( 3) in their final assembled position, wherein the bearing surface (   6 ) for the partial spherical surface ( 4 ) of the sleeve ( 2 ) or of the pivot ( 3 ) is integrated in the inner surfaces of the two housing halves ( 9, 10 ) and these ( 9, 10 ) are surrounded on their outer surfaces ( 11, 12 ) by a metallic ring element ( 8 ) in a positive-locking manner.

FIELD OF THE INVENTION

[0001] The present invention pertains to a ball-and-socket joint,comprising a sleeve or a pivot with a partial spherical surface and abearing shell surrounding the said partial spherical surface in apositive-locking manner with a hollow spherical bearing surface, whichis arranged in a two-part housing, whose housing halves have snap-inelements with detents and locking grooves mutually engaging each other,which lock the two housing halves in the direction of the longitudinalaxis of the sleeve or pivot immovably in relation to one another intheir final assembled position.

BACKGROUND OF THE INVENTION

[0002] In an older suggestion of this type according to DE 100 23 602A1, the bearing shell is designed as a separate component and is clampedbetween the two housing halves. The bearing shell has an at leasttwo-part design and must be fitted in correspondingly accurately for thecorrectly fitting seating of the partial spherical surface of a sleeveand the hollow spherical bearing shell and it also must be clamped inwithout clearance on its outer surface in both housing halves. Thisrequires not only a precision manufacture for correct fit in quantityproduction, but also at least four parts, namely, two housing halves andthe two bearing shells, which must be exactly coordinated with thepartial spherical surfaces of the sleeve or the pivot.

[0003] In a ball-and-socket joint of another type according to DE 19 84453 U1, a ring with a partial spherical surface is clamped on a boltbetween two mirror-symmetrical support pieces, and a divided outer ringwith a partial hollow spherical surface is clamped on the said partialspherical surface in an elastic bush, which is mounted between two snaprings within an opening of a transversal swinging arm. The bolt isarranged between two flanges of a chassis and is secured by means of awasher, a castellated nut and a cotter pin at the end facing away fromthe bolt head. The drawback is a large number of parts, which are to beexactly coordinated with one another and make not only the quantityproduction, but also the assembly of the ball-and-socket jointcomplicated.

SUMMARY OF THE INVENTION

[0004] Based on this state of the art, the basic object of the presentinvention is to simplify a ball-and-socket joint of the type mentionedin the introduction in terms of the assembly and production technologyand to guarantee a correctly fitting seating with weak frictional forcesof the ball-and-socket joint by the force- or displacement-controlledpositioning of the two housing halves during their assembly.

[0005] This object is accomplished according to the present invention inconjunction with the generic features described in the introduction bythe bearing surface for the partial spherical surface of the sleeve orof the pivot being integrated in the inner surfaces of both housinghalves.

[0006] It becomes possible due to this design, the force-controlled ordisplacement-controlled pressing together of the two housing halves, topress together the locking elements during their assembly with theirmutually engaging detents and locking grooves to the extent that thecorrectly fitting seating is obtained between the partial sphericalsurface of the sleeve and of the pivot, on the one hand, and the hollowspherical bearing surface of the bearing shells extending over one otherin a positive-locking manner.

[0007] According to an advantageous embodiment of the present invention,the housing halves are extended over on their outer surface by ametallic ring element in a positive-locking manner. The preferablymetallic ring element extending over the two housing halves preferablyalso acts as a displacement limitation during the pressing together ofthe two housing halves during the assembly. The ring element belongs toa first component, which is coupled in an articulated manner with asecond component that is to be connected to the sleeve or to the pivotvia the ball-and-socket joint. The ring element may also be made ofother suitable materials, e.g., plastic or composites of metal andplastic instead of from the above-mentioned metallic materials.

[0008] According to an especially advantageous embodiment of the presentinvention, a gap extending approximately in parallel to the longitudinalsymmetry axis of the sleeve or of the pivot is provided between thehousing inner parts containing the bearing surfaces and the housingouter parts having the contact surfaces for the ring element. It ispossible due to this gap to enable the housing inner parts having thebearing surfaces to elastically recede to the outside into the gapduring the pressing together. The housing inner parts with their bearingsurfaces are advantageously in contact with the partial sphericalsurface of the sleeve or of the pivot in the locked assembled positionunder a desired spring pretension. The spring pretension can becontrolled by means of the ring-shaped, leaf spring-like recedingbearing surfaces on the basis of the depth of snapping in of the lockingelements of the two housing halves. This ball-and-socket joint makes itpossible to lock the two housing halves with one another in relation tothe partial spherical surface such that either a clearance-freeball-and-socket joint or a ball-and-socket joint that is subject tofriction is created, which will grind itself in automatically tocorrectly fit after a certain number of movements of the joint. At anyrate, this arrangement according to the present invention eliminates thepossibility of a ball-and-socket joint tending to have an undesiredclearance and consequently undesired tilting movements as well as of aball-and-socket joint that is subject to strong frictional forces.

[0009] Finally, this ball-and-socket joint requires only two parts,because the hollow spherical bearing surface is integrated within thetwo housing halves. Not only simple manufacture, but also a likewisesimple and rapid as well as reliable assembly is guaranteed as a result.

[0010] The housing outer parts of the two housing halves advantageouslyengage one another with their cylindrical locking elements during theassembly, wherein the cylindrical locking element of one housing half,which faces the ball head, is alternatingly provided with detents andlocking grooves on its cylindrical outer surface, and the cylindricalinner surfaces of the cylindrical locking element of the other housinghalf, which extends over it, is provided with corresponding lockinggrooves and detents, which engage each other in a barb-like manner.Since the two locking elements with their cylindrical outer surfaces arein contact with the metallic ring element in a correctly fitting mannerand are surrounded by same, it is no longer possible to loosen thelocked connection without destruction.

[0011] It is obvious that the cylindrical surfaces of the lockingelements may alternatively also be provided with locking tongues, as isshown in FIGS. 1 and 3 of the older suggestion DE 100 23 602 A1.

[0012] Finally, any spring pretension of the two housing inner parts inrelation to their bearing surfaces brings about an increase in thelocking forces of the locking element, which are pressed as a resultagainst the metallic ring element, thus increasing the pressure.

[0013] To keep penetrating contaminants and consequently undesiredfrictions that may be associated therewith away from the ball-and-socketjoint, both housing halves are provided with an annular ring each attheir ends and are sealed against the sleeve or the pivot via anentropy-elastic ring sleeve extending over the said annular bead.

[0014] The ring sleeves may be fastened to the housing halves eitherindirectly or directly under elastic pretension or may be connectedthereto by a connection in substance. For example, a two-componentinjection molding method may be used as a connection in substance. Aone-part design of the ring sleeve and the housing half is also withinthe scope of the idea of the present invention.

[0015] While the sleeve or the pivot consists of a proven metal alloy,the housing halves are made of a wear- and heat-resistant plastic, e.g.,polyether imide, polyamide, polyoxymethylene or polyether ether ketone.

[0016] The above-described ball-and-socket joint can be used especiallyadvantageously on a rocker pendulum, on a tie rod or a transversalswinging arm of a motor vehicle.

[0017] The various features of novelty which characterize the inventionare pointed out with particularity in the claims annexed to and forminga part of this disclosure. For a better understanding of the invention,its operating advantages and specific objects attained by its uses,reference is made to the accompanying drawings and descriptive matter inwhich preferred embodiments of the invention are illustrated.

BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In the drawings:

[0019]FIG. 1 is a view of a first embodiment of a ball-and-socket jointin conjunction with a sleeve;

[0020]FIG. 2 is a sectional view along line II-II in FIG. 1;

[0021]FIG. 3 is the enlarged detail III from FIG. 2;

[0022]FIG. 4 is a view of a second embodiment of a ball-and-socket jointin conjunction with a sleeve, which is sealed at both ends by means ofan entropy-elastic ring sleeve against the two housing halves;

[0023]FIG. 5 is a sectional view along line V-V in FIG. 4;

[0024]FIG. 6 is the enlarged detail VI from FIG. 5;

[0025]FIG. 7 is a view of a third embodiment of a ball-and-socket jointin conjunction with a pivot;

[0026]FIG. 8 is a sectional view along line VIII-VIII in FIG. 7;

[0027]FIG. 9 is an enlarged detail IX from FIG. 8; and

[0028]FIG. 10 is a perspective exploded view of the two housing halveswith the ring element without sleeve and pivot.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] Referring to the drawings in particular, parts having the samefunction are designated with the same reference numbers in all figures.

[0030] In the first embodiment according to FIGS. 1 through 3, theball-and-socket joint 1 comprises a sleeve 2 with a partial sphericalsurface 4 and a bearing shell 5 surrounding the partial sphericalsurface 4 in a positive-locking manner with hollow spherical bearingsurfaces 6, which are arranged in a common housing 7. The housing 7 isformed by the two housing halves 9, 10, which are surrounded on theouter surfaces 11, 12 by a metallic ring 8 in a positive-locking manner.This ring 8 belongs to a first component, not shown, which is coupled inan articulated manner via the ball-and-socket joint 1 with a secondcomponent, which is to be connected to the sleeve 2 and is likewise notshown.

[0031] The hollow spherical bearing surface 6 of the partial sphericalsurface 4 is integrated in the housing inner parts 9 a,10 a of the twohousing halves 9, 10.

[0032] As is apparent from FIG. 2 in conjunction with FIG. 3, a gap 14extending approximately in parallel to the longitudinal symmetry axis 13of the sleeve 2 is provided between these housing inner parts 9 a, 10 acontaining the bearing surfaces 6 on the housing outer parts 9 b, 10 bof the two housing halves 9, 10, which said housing outer parts 9 b, 10b have the contact surfaces 11, 12 for the ring element 8. Cylindricallocking elements 15, 16, which mutually extend over each other, arearranged at both housing outer parts 9 b, 10 b. Of these, thecylindrical locking element 15 of the housing half 9 facing the ballhead 4 is provided alternatingly with detents 17 and locking grooves 18on its cylindrical outer surface 15 a, while the cylindrical innersurface 16 a of the locking element 16 of the second housing part 10 isprovided with corresponding locking grooves 18 and detents 17, whichengage one another in a barb-like manner, as is apparent from FIG. 3.

[0033] As can be determined from FIG. 2, each housing half 9, 10 has aring flange 9 c, 10 c each, which is in contact by one lateral surfacewith the ring element 8, whose width B determines the snap-in depth t ofthe two cylindrical locking elements 15, 16. This snap-in depth t isselected in conjunction with the width B of the ring element 8 such thatthe housing inner parts 9 a, 10 a are in contact by their bearingsurfaces 6 with the partial spherical surface 4 of the sleeve 2 or ofthe pivot 3 under a certain spring pretension in the locked assembledposition (see FIGS. 7 through 9). The amount of this spring pretensioncan be controlled by selecting the snap-in depth t of the cylindricallocking elements 15, 16. When the two housing parts 9, 10 are pushed onone another in the direction of the arrows 19, 20, the housing innerparts 9 a, 10 a elastically move outwardly in the direction of thearrows 21 after coming into contact with the partial spherical surface 4until the desired snap-in depth t with the desired spring pretension isreached.

[0034] The snap-in depth t can be reached in both adisplacement-controlled manner and a force-controlled manner, e.g., withthe force that is necessary to lock the housing parts 9, 10 with oneanother in the direction of the arrows 19, 20.

[0035] The second embodiment according to FIGS. 4 through 6 differs fromthe first embodiment according to FIGS. 1 through 3 only in that the twohousing halves 9, 10 are provided with an annular ring 22, 23 each attheir ends and are sealed against the sleeve 2 by means of anentropy-elastic ring sleeve 24, 25 each extending over them. Theball-and-socket joint 1 is protected from penetrating dust and moistureas a result.

[0036] Both housing halves 9, 10 are advantageously made from a wear-and heat-resistant plastic, such as polyether amide, polyamide,polyoxymethylene or polyether ether ketone according to the injectionmolding method.

[0037]FIGS. 7 through 9 show a third embodiment of a ball-and-socketjoint 1, which differs from the two above-described embodiments in thatthe ring element 8 belongs to a component 8a that is coupled via theball-and-socket joint 1 with a second component, which is to beconnected to the pivot 3 and is not shown. The pivot 3 is likewiseprovided with the partial spherical surface 4, which is surrounded bythe correspondingly shaped, hollow spherical bearing surfaces 6 of thebearings 5 integrated within the housing inner parts 9 a, 10 a. Parts ofthe above-described embodiments that have the same function are alsodesignated with the same reference numbers.

[0038]FIG. 10 shows the exploded views of the housing half 9 and of thehousing halve 10 with their housing outer parts 9 b, 10 b, as well as ofthe ring flanges 9 c, 10 c. The cylindrical locking elements 15, 16 withtheir barb-like detents 17 and with the locking grooves 18 locatedbetween them can be clearly recognized. The annular rings 22, 23correspond to the above-described embodiments.

[0039] While specific embodiments of the invention have been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

1. ball-and-socket joint, comprising a sleeve or a pivot with a partialspherical surface and with a bearing shell surrounding this partialspherical surface in a positive-locking manner with a hollow sphericalbearing surface, which is arranged in a two-part housing, whose housinghalves have locking elements with detents and locking grooves mutuallyengaging each other, which lock the two housing halves in the directionof the longitudinal axis of the sleeve or of the pivot immovably inrelation to one another in their final assembled position, characterizedin that the said bearing surface (6) for the said partial sphericalsurface (4) of the said sleeve (2) or of the said pivot (3) isintegrated within the inner surfaces of the said two housing halves (9,10):
 2. Ball-and-socket joint in accordance with claim 1, characterizedin that the said housing halves (9, 10) are extended over on their saidouter surfaces (11, 12) by a said metallic ring element (8) in apositive-locking manner.
 3. Ball-and-socket joint in accordance withclaim 1, characterized in that the said ring element (8) belongs to asaid first component (8a), which is coupled via the said ball-and-socketjoint (1) with a second component that is to be connected to the saidsleeve (2) or to the said pivot (3).
 4. Ball-and-socket joint inaccordance with claim 1 or 2, characterized in that a said gap (14)extending approximately in parallel to the said longitudinal symmetryaxis (13) of the said sleeve (2) or of the said pivot (3) is providedbetween the said housing inner parts (9 a, 10 a) containing the saidbearing surfaces (6) and the said housing outer parts (9 b, 10 b) of thesaid two housing halves (9, 10), which said housing outer surfaces havethe said contact surfaces (11, 12) for the said ring element (8). 5.Ball-and-socket joint in accordance with one of the claims 1 through 3,characterized in that the said housing inner parts (9 a, 10 a) are incontact by their said bearing surfaces (6) with the said partialspherical surface (4) of the said sleeve (2) or of the said pivot (3)under spring pretension.
 6. Ball-and-socket joint in accordance withclaim 4, characterized in that the amount of the spring pretension iscontrolled by displacement as a function of the said snap-in depth (t)of the said locking elements (15, 16) or is controlled by forceaccording to the force with which the said two housing halves (9, 10)are pressed together.
 7. Ball-and-socket joint in accordance with one ofthe claims 1 through 5, characterized in that the said housing outerparts (9 b, 10 b) of the said two housing halves (9, 10) extend overeach other with said cylindrical locking elements (15, 16), of which thesaid cylindrical locking element (15) of one said housing half (9),which faces the said ball head (4), is provided alternatingly with saiddetents (17) and said locking grooves (18) on its said partialcylindrical outer surface (15 a), and the said cylindrical inner surface(16 a) of the said cylindrical locking element (16) of the said otherhousing half (10) extending over same is provided with saidcorresponding locking grooves (18) and said detents (17), which engageeach other in a barb-like manner.
 8. Ball-and-socket joint in accordancewith one of the claims 1 through 6, characterized in that both saidhousing halves (9, 10) are provided with a said annular ring (22, 23)each at their ends and are sealed against the said sleeve (2) or thesaid pivot (3) by means of a said entropy-elastic ring sleeve (24, 25)extending over the said annular ring.
 9. Ball-and-socket joint inaccordance with one of the claims 1 through 7, characterized in that thesaid housing halves (9, 10) are made of a wear- and heat-resistantplastic, such as polyether imide, polyamide, polyoxymethylene orpolyether ether ketone.
 10. Ball-and-socket joint in accordance with oneof the claims 1 through 8, for use in a rocker pendulum, on a tie rod oron a transversal swinging arm of a motor vehicle.
 11. Ball-and-socketjoint in accordance with one of the claims 8 through
 10. characterizedin that the said ring sleeves (24, 25) are connected to the said housinghalves (9, 10) by a connection in substance.